This invention relates to an improved mold equipment which can mold a synthetic resin such as polyurethane foam.
Hard and semi-hard polyurethane foams are popular in fields such as a rolling stock cushions and furniture cushions. These foams are manufactured in a hot mold equipment and semi-hot mold equipment. In the mold equipment, a mold transfer conveyor is horizontally arranged in an endless fashion at a certain level on a floor and a mold is circulatingly moved such that the infusion of a solution for foam, curing under heating, cooling and mold releasing are effected at a speed of about 5 m/min. In this method, the apparatus becomes bulky and the manufacturing line has a great total length (usually more than 100 m), making it difficult to obtain a saving in energy and labor.
In the curing step, heating is effected at 200.degree. to 300.degree. C. and the subsequent step requires a longer cooling zone in which air or a cooling shower is applied. Use is normally made of a heating oven using hot air as a heat source. The inlet and outlet of the metal mold are opened and closed each time the metal mold is moved into and out of the oven. Thus, a lowering in heat efficiency, as well as a greater consumption of a heavy oil due to the dissipation of the hot air, is involved.
A conveyor is continuously run over the whole length of the manufacturing line and the processing time is adjusted for each step. If the whole process is treated at the same speed, an attendant on each process is required (usually 10 or more attendants).
It is accordingly an object of this invention to provide a mold equipment which has a shorter manufacturing line, can achieve a saving in labor and energy, is lower in equipment cost and which can easily release a foamed article from a mold.